Love Jessica's Simpson's Line? Now it's a Sister Act!

Past cover stars Jessica and Ashlee Simpson are becoming more than sisters—they're business partners! Jessica Simpson's sexy, affordable clothing company, which is valued at a billion dollars (yes, we said billion!), is expanding and Ashlee's coming on board to run the younger style division. She'll be designing edgy, rocker-ish looks—similar to her own signature style—that will hit stores this fall.